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chromium toxicity

Chad M Thompson, Jeffrey C Wolf, Alene McCoy, Mina Suh, Deborah M Proctor, Christopher R Kirman, Laurie C Haws, Mark A Harris
High concentrations of hexavalent chromium (Cr(VI)), captan, and folpet induce duodenal tumors in mice. Using standardized tissue collection procedures and diagnostic criteria, we compared the duodenal histopathology in B6C3F1 mice following exposure to these 3 carcinogens to determine whether they share similar histopathological characteristics. B6C3F1 mice ( n = 20 per group) were exposed to 180 ppm Cr(VI) in drinking water, 12,000 ppm captan in feed, or 16,000 ppm folpet in feed for 28 days. After 28 days of exposure, villous enterocyte hypertrophy and mild crypt epithelial hyperplasia were observed in all exposed mice...
January 1, 2017: Toxicologic Pathology
T V Ramachandra, P B Sudarshan, M K Mahesh, S Vinay
Heavy metals are one among the toxic chemicals and accumulation in sediments and plants has been posing serious health impacts. Wetlands aid as kidneys of the landscape and help in remediation through uptake of nutrients, heavy metals and other contaminants. The analyses of macrophytes and sediment samples help in evaluating pollution status in aquatic environment. In this study concentration of six heavy metals (Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb) and Zinc (Zn)) were assessed in sediment and dominant macrophyte samples collected from Bellandur Lake, largest Lake of Bangalore, India...
November 17, 2017: Journal of Environmental Management
Vibha Sinha, Kannan Pakshirajan, Rakhi Chaturvedi
In the current industrial scenario, chromium (Cr) as a metal is of great importance, but poses a major threat to the environment. Phytoremediation provides an environmentally sustainable, ecofriendly, cost effective approach for environmental cleanup of Cr. This review presents the current status of phytoremediation research with particular emphasis on cleanup of Cr contaminated soil and water systems. It gives a detailed account of the work done by different authors on the Cr bioavailability, uptake pathway, toxicity and storage in plants following the phytoextraction mechanism...
November 17, 2017: Journal of Environmental Management
Cheng-Tien Wu, Chen-Yuan Chiu, Chun-Fa Huang, Fu-Chuo Peng, Shing-Hwa Liu
Steady-fiber granule (SFG) is a functional food mixture that is composed of four major ingredients, resistant maltodextrin, white kidney bean (Phaseolus vulgaris) extract, mulberry leaf (Morus alba L.) extract, and niacin-bound chromium complex. This study focused on determining the safety of SFG. Genotoxicity and 28-day oral toxicity were evaluated. SFG did not induce mutagenicity in the bacterial reverse mutation assay using five Salmonella typhimurium strains (TA98, TA100, TA102, TA1535, and TA1537) in the presence or absence of metabolic activation (S9 system)...
November 16, 2017: Regulatory Toxicology and Pharmacology: RTP
Imad Aharchaou, Jean-Sebastien Py, Sebastien Cambier, Jean-Luc Loizeau, Geert Cornelis, Philippe Rousselle, Eric Battaglia, Davide A L Vignati
Despite the consensus about the importance of chemical speciation in controlling the bioavailability and ecotoxicity of trace elements, detailed speciation studies during laboratory ecotoxicity testing remain scarce, contributing to uncertainty when extrapolating laboratory findings to real field situations in risk assessment. We characterized the speciation and ecotoxicological effects of Cr(III) and Cr(VI) in the ISO medium for algal ecotoxicity testing. Total and dissolved (<0.22 μm) Cr concentrations showed little variability in media spiked with Cr(VI) , while dissolved Cr concentration decreased by as much as 80% over 72 hours in medium amended with Cr(III) ...
November 18, 2017: Environmental Toxicology and Chemistry
Kelly A Shipkowski, Christopher M Sheth, Matthew J Smith, Michelle J Hooth, Kimber L White, Dori R Germolec
Sodium dichromate dihydrate (SDD), an inorganic compound containing hexavalent chromium (Cr(VI)), is a common environmental contaminant of groundwater sources due to widespread industrial use. There are indications in the literature that Cr(VI) may induce immunotoxic effects following dermal exposure, including acting as both an irritant and a sensitizer; however, the potential immunomodulatory effects of Cr(VI) following oral exposure are relatively unknown. Following the detection of Cr(VI) in drinking water sources, the National Toxicology Program (NTP) conducted extensive evaluations of the toxicity and carcinogenicity of SDD following drinking water exposure, including studies to assess the potential for Cr(VI) to modulate immune function...
December 2017: Journal of Immunotoxicology
Mohammad Dinari, Atefeh Haghighi
In this study, novel nanocomposites (NCs) of aromatic polyamide (PA) and surface modified ZnO nanoparticle with s-triazine heterocyclic ring was introduced for efficient removal of toxic hexavalent chromium (VI) from aqueous solution. The surface of ZnO nanoparticle was modified by s-triazine core silane coupling agent (ZnO-TSC) and PA/ZnO-TSC NCs with different amount of ZnO-TSC nanoparticles (0, 5, 10 and 15wt%) were prepared by ultrasonic irradiation. The synthesized PA/ZnO-TSC NCs were characterized by FT-IR, XRD, FE-SEM, TEM and TGA methods...
March 2018: Ultrasonics Sonochemistry
Huawen Han, Zhenmin Ling, Tuoyu Zhou, Rong Xu, Yongxing He, Pu Liu, Xiangkai Li
Microbes can reduce hexavalent chromium Cr (VI) to the less toxic and soluble trivalent Cr (III). Copper stimulates microbial reduction of Cr (VI) by the Bacillus, Ochrobactrum, and Gluconobacter species; however, the mechanism remains unclear. In our study, the rate of Cr (VI) reduction by Staphylococcus aureus LZ-01 was increased by 210 % when supplemented with 60 μM Cu (II). A putative NAD(P)H-flavin oxidoreductase gene (nfoR) was upregulated under Cr (VI) stress. NfoR-knockout mutant displayed impaired reduction of Cr (VI) and Cu (II)-enhanced Cr (VI) reduction by nfoR isogenic mutant was attenuated in the presence of Cu (II)...
November 13, 2017: Scientific Reports
Romana Manzoor, Tingwan Zhang, Xuejiao Zhang, Min Wang, Jin-Fen Pan, Zhumei Wang, Bo Zhang
With the development of industrialization and urbanization, metal and metalloid pollution is one of the most serious environmental problems in China. Current contamination status of metals and metalloid and their potential ecological risks along China's coasts were reviewed in the present paper by a comprehensive study on metal contents in marine waters and sediments in the past few decades. The priority metals/metalloid cadmium (Cd), mercury (Hg), chromium (Cr), lead (Pb), and arsenic (As), which were the target elements of the designated project "Comprehensive Prevention and Control of Heavy Metal Pollution" issued by the Chinese government in 2011, were selected considering their high toxicity, persistence, and prevalent existence in coastal environment...
November 10, 2017: Environmental Science and Pollution Research International
Jianjun Zhou, Hongrui Ma, Mao Gao, Wenyue Sun, Chao Zhu, Xiangping Chen
The application or disposal of char derived from tannery sludge is directly influenced by the mobility and bioavailability of Cr during pyrolysis process. This study focused on the changes of Cr speciation and organic matter in tannery sludge during low-temperature pyrolysis (100-400 °C) to evaluate the toxicity of char in terms of the leaching possibility of Cr. The results showed that (1) lower char yield and more porous structure were observed after pyrolysis. (2) Higher pyrolysis temperature increased Cr content in the char; however, Cr in this case was converted into the residual fraction which minimized its bioavailability therefore lowers its potential risk to the environment...
November 10, 2017: Environmental Science and Pollution Research International
Yafei Wang, Hong Su, Xin Song, Samuel Selorm Fiati Kenston, Jinshun Zhao, Yuanliang Gu
With the rapid economic development in recent years, China is facing a great challenge due to heavy metal pollution. The heavy metals may enter the human body through ingestion of aqua products to cause great health risks. In the present study, the inhibitory effects of luteolin on the combined toxicity of multi-heavy metals (including zinc, manganese, lead, copper, cadmium, mercury, chromium and nickel) were investigated in HL7702 hepatocyte cells. An MTT assay demonstrated that 20 µM luteolin significantly alleviated the multi-heavy metal mixture-induced cell death and morphological changes...
October 27, 2017: International Journal of Molecular Medicine
Jian Yin, Ai-Ping Wang, Wan-Fang Li, Rui Shi, Hong-Tao Jin, Jin-Feng Wei
The present work aims to explore the time-response (from 24 h to 96 h) characteristic and identify early potential sensitive biomarkers of copper (Cu) (as copper chloride dihydrate), cadmium (Cd) (as cadmium acetate), lead (Pb) (as lead nitrate) and chromium (Cr) (as potassium dichromate) exposure in adult zebrafish, focusing on reactive oxygen species (ROS), SOD activity, lipid peroxidation and gene expression related to oxidative stress and inflammatory response. Furthermore, the survival rate decreased apparently by a concentration-dependent manner after Cu, Cr, Cd and Pb exposure, and we selected non-lethal concentrations 0...
October 28, 2017: Fish & Shellfish Immunology
Mac Gifford, Mikhail Chester, Kiril Hristovski, Paul Westerhoff
Treatment of drinking water decreases human health risks by reducing pollutants, but the required materials, chemicals, and energy emit pollutants and increase health risks. We explored human carcinogenic and non-carcinogenic disease tradeoffs of water treatment by comparing pollutant dose-response curves against life cycle burden using USEtox methodology. An illustrative wellhead sorbent groundwater treatment system removing hexavalent chromium or pentavalent arsenic serving 3200 people was studied. Reducing pollutant concentrations in drinking water from 20 μg L(-1) to 10 μg L(-1) avoided 37 potential cancer cases and 64 potential non-cancer disease cases...
October 9, 2017: Water Research
I Orjales, C Herrero-Latorre, M Miranda, F Rey-Crespo, R Rodríguez-Bermúdez, M López-Alonso
The present study aimed to evaluate trace mineral status of organic dairy herds in northern Spain and the sources of minerals in different types of feed. Blood samples from organic and conventional dairy cattle and feed samples from the respective farms were analysed by inductively coupled plasma mass spectrometry to determine the concentrations of the essential trace elements (cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), iodine (I), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se) and zinc (Zn)) and toxic trace elements (arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb))...
November 6, 2017: Animal: An International Journal of Animal Bioscience
Ramkrishna Nirola, Mallavarapu Megharaj, Avudainayagam Subramanian, Palanisami Thavamani, Kavitha Ramadass, Rupak Aryal, Christopher Saint
Chromium from tannery waste dump site causes significant environmental pollution affecting surrounding flora and fauna. The primary aims of this study were to survey vegetation, investigate the degree of soil pollution occurring near tannery waste dump site and make a systematic evaluation of soil contamination based on the chromium levels found in plants and earthworms from the impacted areas. This paper presents the pollution load of toxic heavy metals, and especially chromium, in 10 soil samples and 12 species of plants...
November 3, 2017: Environmental Science and Pollution Research International
Nalan Oya San Keskin, Asli Celebioglu, Omer Faruk Sarioglu, Tamer Uyar, Turgay Tekinay
Cyclodextrins (CD) are cyclic oligosaccharides produced from the enzymatic degradation of starch as a white powder form; on the other hand, they can be transformed into ultrathin electrospun fiber form by electrospinning technique. The electrospun cyclodextrin fibers (CD-F) can be quite attractive materials to encapsulate bacteria for bioremediation purposes. For instance, CD-F not only serve as a carrier matrix but also it serves as a feeding source for the encapsulated bacteria. In the present study, we demonstrate a facile approach by encapsulation of bacteria into CD-F matrix for wastewater treatment application...
October 18, 2017: Colloids and Surfaces. B, Biointerfaces
Li-Chun Wu, Teh-Hua Tsai, Man-Hai Liu, Jui-Ling Kuo, Yung-Chu Chang, Ying-Chien Chung
The extensive use of Cr(VI) in many industries and the disposal of Cr(VI)-containing wastes have resulted in Cr(VI)-induced environmental contamination. Cr(VI) compounds are associated with increased cancer risks; hence, the detection of toxic Cr(VI) compounds is crucial. Various methods have been developed for Cr(VI) measurement, but they are often conducted offsite and cannot provide real-time toxicity monitoring. A microbial fuel cell (MFC) is an eco-friendly and self-sustaining device that has great potential as a biosensor for in situ Cr(VI) measurement, especially for wastewater generated from different electroplating units...
October 27, 2017: Sensors
Hongxing Chen, Zhongbao Guo, Yu Zhou, Dan Li, Lei Mu, Paul L Klerks, Yongju Luo, Lingtian Xie
We previously demonstrated that chronic exposure to hexavalent chromium (Cr(VI)) causes a variety of adverse effects in the Japanese medaka (Oryzias latipes). The present study investigated the transition of acute to chronic effects by assessing the influences of Cr(VI) exposure concentration and exposure duration on Cr accumulation and their effects on fish growth and antioxidant physiology. Juvenile fish were exposed to 0.05, 0.5, 4 or 8mg/L Cr(VI) for 28 days. Endpoints were evaluated on days 3, 7, 14, 21 and 28...
October 22, 2017: Ecotoxicology and Environmental Safety
Vincent Nartey Kyere, Klaus Greve, Sampson Manukure Atiemo, James Hawkins Ephraim
The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld GPS, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn)...
October 17, 2017: Environmental Health and Toxicology
Lotfi Ben Tahar, Mohamed Habid Oueslati, Mustafa Jaipallah Abdelmageed Abualreish
Nowadays there is a continuously increasing worldwide concern for the development of efficient wastewaters treatment technologies. Among the heavy metal ions, chromium holds a distinct position due to its high toxic nature to biological systems. This study aims to assess magnetite derivatives nanoparticles for the removal of Cr(VI) species. Crystalline magnetite-rich (Magn) and pure maghemite (Magh) nanoparticles were produced by the polyol method and by subsequent heat treatment of Magn, respectively. The XRD analysis confirmed the formation of nanosized single phase cubic spinels with a cell parameter of 8...
October 12, 2017: Journal of Colloid and Interface Science
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